SCOTTSDALE, Ariz. -- When Dave Duncan was 21 years old, he was calling pitches for future Hall-of-Famer Catfish Hunter.
He'd go on to catch the likes of other Cooperstown nobles Gaylord Perry, Jim Palmer and Rollie Fingers, while guiding Vida Blue to a 20-win season in 1971 and helping Jim Perry to 17 wins in 1974 -- his final winning year.
And that was just the precipice of his contribution to pitchers.
As a pitching coach for the St. Louis Cardinals, Oakland Athletics, Chicago White Sox, Seattle Mariners and Cleveland Indians, Duncan ascended to legendary status, considered by one Diamondbacks front office member to be "the greatest pitching coach the game has ever known."
After being out of coaching for the last two seasons, Duncan is now with the Diamondbacks for the 2014 season as a special assistant to general manager Kevin Towers -- serving as a pitching consultant to an Arizona staff which finished in the bottom half of the National League in all major statistical categories last season.
With the Diamondbacks, Duncan is now charged with the task of helping first-time major league pitching coach Mike Harkey to learn the ropes of the role. Together, they'll look to rectify the issues of last year's Diamondbacks pitchers.
The 2014 Diamondbacks had their first workout on Friday and Towers and manager Kirk Gibson are sure that Duncan is already making a difference.
"He's a very interesting man with incredible knowledge and just an incredible résumé," Towers told the media at Salt River Fields on Friday.
"Just his mere presence -- you know, watching him today standing behind your pitchers -- makes you feel pretty good about the Diamondbacks."
According to Gibson, Duncan lit up the room when he shared at last week's organizational meetings. He spoke for 30 minutes and had the room on the edge of their seat.
"I shared 20 of the 30 minutes with our pitchers this morning," Gibson said Friday.
"(It was) very impactful, well laid out; (I) couldn't have said it better," he went on.
Given his track record and history of leading pitchers to greatness -- be it Hunter or Palmer from behind the plate or Tom Seaver, Dennis Eckersley and Chris Carpenter from the dugout -- Duncan's level of respect within the game, and the Diamondbacks organization, is impossible to quantify.
"Especially when he speaks, I think it really sinks in and guys are going to be receptive," Towers said.
Duncan entered major league baseball 50 years ago and the knowledge he wields is just beginning to impact the troubled throng of Diamondbacks pitchers. Over the first 12 days of spring training, for example, Diamondbacks pitchers will throw on only four days -- a practice, Gibson said, which was instituted by Duncan as a flight from a workload which used to be much heavier.
"He's sharing info with us and that's not just good information, but he's sharing how he got it and arrived there," Gibson said.
Diamondbacks pitchers and catchers reported to Salt River Fields on Thursday and had their first workout on Friday. Duncan will help to lead not only the Diamondbacks major league pitching staff, but also lower-level coaches and pitchers.